Retrotec Residential Pressure & Air Leakage - Manual (Page 9)

Page 9 of 75
To calculate annual cooling cost
Use the following equation:
0.026 ×𝐶𝐷𝐷 ×𝐹𝑢𝑒𝑙 𝑃𝑟𝑖𝑐𝑒 ×𝐶𝐹𝑀50
𝑁 ×𝑆𝐸𝐸𝑅

CDD is the cooling degree days (base 70° F) for the building location

Fuel Price is the cost of electricity in dollars per kWh.

N is the Energy Climate Factor from the Climate Information Screen

SEER is the SEER rating for the air conditioner.
1.5 How Blower Doors Measure Air Leakage
All Blower Door Systems consist of a door
panel (which temporarily seals an open
doorway), and a calibrated fan (which is
installed in the panel). Fan speed is
controlled either manually (with a manual
dial) or automatically (with a digital gauge
or specially designed software). A
calibrated gauge can display results in a
variety of units. Computer software can
display similar results but will add more
complex data analysis and automatic
testing.
See Retrotec's Blower Door Operation
Manual for more information on how to
install and run a Blower Door system.
Figure 5: A Blower Door can be used to measure whole house leakage from any exterior doorway.
1.6 Reduce causes of Bias pressure to get good test results
Wind blowing across the tip of a tube will cause a significant pressure to appear on the gauge. High fluctuations
of bias (baseline) pressures on the gauge (greater than 2 Pa) are a good indication that wind may be a large
source of error.
Figure 4: Components of a Blower Door system.